Computing devices can have several operating states. Each state can be associated with a level of availability of the computing device and each state can have a related amount of power. It is typical for the computing device to transition from a first operating state with a relatively higher power to a second operating state with a relatively lower power if the computing device has been idle for a predetermined period of time. For example, a computing device can be configured to power down a display when the computing device has been idle for an amount of time. To recover from the lower power state to the higher power state, the user can typically move a mouse or touch a keyboard key.
Some states (such as sleep states) can have very low amounts of power associated with them. As a consequence, it can take longer to recover from this low power state and return to a regular operating state. A second consequence is that simply moving the mouse or pressing a keyboard is usually not sufficient to wake the device. This behavior can be due to the fact that at very low power states, many device interfaces have been powered down to save power. Once the interfaces have been powered down, they can be unresponsive to external stimulus. For many computing devices, the only recovery from very low power states can be by the use of the main power switch. Use of the power switch can be non-intuitive since the user did not power down the computing device.
Therefore, what is desired is a reliable way for a computing device to recover from a very low power state, when traditional device interfaces can be powered down, without using the main power switch.